The Nutrition for Life Cohort was created to assess the nutritional consequences of HIV infection. Initially, the focus of the project was on wasting. Recently, HIV treatment has been revolutionized by the advent of highly active anti-retroviral therapy (HAART). Despite the virologic and clinical benefits of new anti-HIV therapies, weight loss remains a common finding in our population. In addition, other nutritional problems, such as fat redistribution and metabolic alterations, have been attributed to use of protease inhibitors. This renewal, which comprises 4 projects and 5 cores , will maintain the original cohorts of adults (425) and children (151) with HIV. While the hypotheses from the original grant will continue to be explored as additional longitudinal data are collected, the major emphasis of this renewal is directed to a series of new hypotheses related to nutrition and HIV in the era of HAART. Project 1 will maintain the adult cohort; the new aims are to determine whether nutrition is a predictor of clinical outcome independent of virologic status of anti-HIV treatments and to define the effects of HAART on nutritional status. Additional studies will examine the nutritional effects of GI abnormalities and the impact of liver disease. Project 2 will examine the effect of exercise training in functional status in patients with HIV wasting and the effect of exercise on abdominal visceral fat and insulin resistance in patients with HIV-associated fat redistribution. Project 3 will study metabolic aspects of rat redistribution, insulin resistance and dyslipidemias related to HIV and treatment with protease inhibitors. Project 4 will continue to follow the pediatric NFL cohort. New goals include metabolic quantification of protein loss and an exercise intervention study; in addition, the effects of HAART in children will be examined along with evaluation of an intervention therapy. The strengths of this program include an accomplished group of investigators who have a track record of working together, all of whom have remained with NFL since its inception; large cohorts of adults and children, many recruited before the HAART era and now receiving various forms of treatment; a diverse cohort (38% non- white and 27% women); and a high incidence (33%) of significant weight loss.